Life might not offer many second chances, but presidential debates do, and President Barack Obama will have his Tuesday.

Now that the vice presidential contest is over, all eyes turn to round two of Obama and Mitt Romney.

It will have been a long two weeks for the president, who has gone around the country saying he was too polite and conceding, basically, that his clock is shiny after Romney cleaned it in the first debate last week. The time has flown by for the Republican rival, with polls and his mood in an obvious uptick.

Going into the second debate at Hofstra University in Hempstead, N.Y., the race has tightened.

Conventional wisdom has held that debates mostly reinforce the choices that viewers have already made. But in this election season, perhaps as in none before, debates have mattered. They are making candidates — and breaking some. Just ask Rick Perry.

For the first presidential faceoff, 67 million viewers tuned in — up 28 percent from the first debate in 2008 between Obama and John McCain. And if history is an indicator, the next might be bigger. In 2008, the second debate captured more viewers.

This time, there is little doubt that voters’ interest is piqued by whether and how Obama will retool his performance — or if a repeated superior showing by Romney can deliver the election.

The format will be different, a town-hall style where undecided audience members ask the questions. Domestic and foreign policy alike are on the table. It makes the topics perhaps a little less predictable.

Those who wonder whether a second debate can make any difference after a lousy performance in the first would do well to look back to 1984.

President Ronald Reagan seemed listless and a little lost in his first matchup with Walter Mondale, raising the specter of whether the 73-year-old was too old to serve a second term.

The second time, he again muffed some facts. But what people remember is when Reagan, asked if he were too old for the presidency, deadpanned: “I will not make age an issue of this campaign. I am not going to exploit, for political purposes, my opponent’s youth and inexperience.”